Upgrade to Pro — share decks privately, control downloads, hide ads and more …

Parsing Binary Data

B5b39c8f21b5bb1ab97852ed32c888ab?s=47 Jan Krutisch
June 29, 2012
Programming
0
69

Parsing Binary Data

A lighting talk about parsing binary data in ruby with bindata gem.

B5b39c8f21b5bb1ab97852ed32c888ab?s=128

Jan Krutisch

June 29, 2012
Tweet

More Decks by Jan Krutisch

See All by Jan Krutisch
B5b39c8f21b5bb1ab97852ed32c888ab?s=48 halfbyte
3
120
B5b39c8f21b5bb1ab97852ed32c888ab?s=48 halfbyte
0
140
B5b39c8f21b5bb1ab97852ed32c888ab?s=48 halfbyte
0
35
B5b39c8f21b5bb1ab97852ed32c888ab?s=48 halfbyte
0
110
B5b39c8f21b5bb1ab97852ed32c888ab?s=48 halfbyte
0
1.5k
B5b39c8f21b5bb1ab97852ed32c888ab?s=48 halfbyte
0
140
B5b39c8f21b5bb1ab97852ed32c888ab?s=48 halfbyte
0
89
B5b39c8f21b5bb1ab97852ed32c888ab?s=48 halfbyte
0
140
B5b39c8f21b5bb1ab97852ed32c888ab?s=48 halfbyte
0
61

Other Decks in Programming

See All in Programming
B49933741d74e122bc1314b2975e9fc9?s=48 mrtc0
1
170
3138f3848e96b7dfc3dba2113bcb43e7?s=48 tmyk110
1
170
E0e036f89c14b3e59640318eedf9670b?s=48 bkuhlmann
4
300
0ed10d1154c696886ca483fe827cb299?s=48 thatjeffsmith
0
1.5k
A93d5da318eccb590724323cbc80f649?s=48 kodetr
0
150
E0e036f89c14b3e59640318eedf9670b?s=48 bkuhlmann
6
710
D76231a2114896dfcc7b79ac69558b79?s=48 yosuke_furukawa
PRO
1
330
02ca2dc42e6d88c692a21b18200796a1?s=48 shun_oshidari
6
2.9k
Bbb17eeeecd3d9d06f4db310ab630a12?s=48 borkdude
1
180
88ad4f75d7c84fcf560bb6205c52e8c1?s=48 dnskimo
7
1.4k
Dc5157c1e1b11923f4cdd210ee27d4af?s=48 patorash
0
140
7beed3a6fa39e12c9e873b903e4d9244?s=48 samjulien
0
370

Featured

See All Featured
F68cb25ae3e5c2106997454b13b7737d?s=48 brad_frost
157
6.5k
053e75a5b48b44d6dd0612795dfb326d?s=48 notwaldorf
19
2.1k
20bfe76b3d6105641f879fe45cfc9272?s=48 bkeepers
PRO
322
53k
E4f5d494ebdc9e7cce1aecf3ce3e8bc1?s=48 shpigford
370
42k
64827b31aef81498662e8af4bd6d5157?s=48 jonrohan
1021
390k
A9a491b0fcbe0fbce3d64063a37add99?s=48 rmw
12
870
170b760e0147792d0140e59ec78e9893?s=48 eitanlees
115
10k
D8fc2580cfaca035f666d9e4ee79a7f7?s=48 mongodb
23
3.9k
3ab1249be442027903e1180025340b3f?s=48 reverentgeek
167
7.3k
7653c7c449918ff6542880a8c284f5e7?s=48 jponch
103
5.1k
D47656e20ff5e42f125fc5ea0fd636c6?s=48 tmm1
61
9.9k
15f2b8221f247985a27a627d2ece72f0?s=48 pauljervisheath
195
15k

Transcript

  1. Parsing and Writing Binary Data in Ruby Jan Krutisch @halfbyte

    jan.krutisch@mindmatters.de

  2. señor developer

  3. None

  4. Protracker "mod" files

  5. Binary Format

  6. None

  7. ‣ Instrument Metadata ‣ Sample Data ‣ Pattern Data ‣

    Sequence Data Mod File Contents

  8. ‣ Instrument Metadata ‣ Sample Data ‣ Pattern Data ‣

    Sequence Data Mod File Contents Array of Structs (=Array of Hashes)

  9. ‣ Instrument Metadata ‣ Sample Data ‣ Pattern Data ‣

    Sequence Data Mod File Contents Array of Structs (=Array of Hashes) Array of Blobs

  10. ‣ Instrument Metadata ‣ Sample Data ‣ Pattern Data ‣

    Sequence Data Mod File Contents Array of Structs (=Array of Hashes) Array of Blobs Arrays of Arrays of Arrays of Structs

  11. ‣ Instrument Metadata ‣ Sample Data ‣ Pattern Data ‣

    Sequence Data Mod File Contents Array of Structs (=Array of Hashes) Array of Blobs Arrays of Arrays of Arrays of Structs Array of Integers

  12. Simple Approach

  13. Serializer / Deserializer

  14. Different Datatypes

  15. Protracker Datatypes

  16. Protracker Datatypes ‣ 8Bit signed binary blobs

  17. Protracker Datatypes ‣ 8Bit signed binary blobs ‣ UInt8

  18. Protracker Datatypes ‣ 8Bit signed binary blobs ‣ UInt8 ‣

    UInt16 (Endianness?)

  19. Protracker Datatypes ‣ 8Bit signed binary blobs ‣ UInt8 ‣

    UInt16 (Endianness?) ‣ \0-Terminated/Padded Strings

  20. Protracker Datatypes ‣ 8Bit signed binary blobs ‣ UInt8 ‣

    UInt16 (Endianness?) ‣ \0-Terminated/Padded Strings ‣ Int4 (Yes, that‘s a signed halfbyte)

  21. And this...

  22. None

  23. Procedural Mess

  24. Declarative

  25. gem "bindata"

  26. class ProtrackerModule < BinData::Record endian :big string :name, :length =>

    20, :trim_padding => true array :samples, :type => Sample, :length => 31 uint8 :pattern_table_length uint8 :unused array :pattern_table, :type => :uint8, :initial_length => 128 [...]

  27. class ProtrackerModule < BinData::Record endian :big string :name, :length =>

    20, :trim_padding => true array :samples, :type => Sample, :length => 31 uint8 :pattern_table_length uint8 :unused array :pattern_table, :type => :uint8, :initial_length => 128 [...]

  28. class ProtrackerModule < BinData::Record endian :big string :name, :length =>

    20, :trim_padding => true array :samples, :type => Sample, :length => 31 uint8 :pattern_table_length uint8 :unused array :pattern_table, :type => :uint8, :initial_length => 128 [...]

  29. class ProtrackerModule < BinData::Record endian :big string :name, :length =>

    20, :trim_padding => true array :samples, :type => Sample, :length => 31 uint8 :pattern_table_length uint8 :unused array :pattern_table, :type => :uint8, :initial_length => 128 [...]

  30. class ProtrackerModule < BinData::Record endian :big string :name, :length =>

    20, :trim_padding => true array :samples, :type => Sample, :length => 31 uint8 :pattern_table_length uint8 :unused array :pattern_table, :type => :uint8, :initial_length => 128 [...]

  31. array :patterns, :type => Pattern, :initial_length => lambda { pattern_table.max

    + 1 }
  32. None

  33. Demo

  34. señor developer http://senordevelopershop.spreadshirt.de/ (europe) http://senordeveloper.spreadshirt.com/ (intl)